I have always run the 6moa rmr. I thought that was the bees knees until I mounted a R1 6moa on my new X-Five. Holy cow, what a difference. I would lose my dot occasionally in the rmr. The R1 is awesome! It’s probably not as durable as an rmr but for USPSA matches it will be just fine. I shot 2 matches with the X5/R1 and I was beating people that I have never beat before.